Collagen is the most abundant structural protein in the extracellular matrix (ECM), providing strength, organization, and integrity to different bodily tissues including the skin and joints. As we age, collagen deposits in the body naturally decline, causing tissues to loss their flexibility and integrity, requiring external interventions to manage this loss. This edition highlights four recent studies involved in various collagen benefits, including skin health, metabolic syndrome, and sleep quality.  

Anti-Obesity Effects of a Collagen with Low Digestibility and High Swelling Capacity: A Human Randomized Control Trial 

Obesity is a multifactorial disease that affects millions around the world, to which point it is now considered an epidemic of the 21st century. Excessive body weight, the main hallmark of obesity, contributes to numerous diseases and mortality. Therefore, there is a great effort to improve dietary habits and physical activity to control and prevent excessive weight gain. Interest in new strategies, such as bioactive compounds contributing to satiety, have increased. This study evaluated the potential anti-obesity effects of bovine (cow) collagen in an in vitro acid-medium that simulates gastric conditions, investigating postprandial levels of ghrelin in rats, and a human randomized, parallel intervention study. The human intervention study aimed to explore the potential anti-obesity effects of cow collagen which were technologically modified to increase the amount of water content and expand in volume under acidic pH conditions. Sixty-four overweight/obese subjects were randomized to follow healthy dietary recommendations alone (control group) or with two protein bars per day that were enriched with 20 g of collagen (collagen group) for 12 weeks. Anthropometric and biochemical measurements were assessed in all participants. The in vitro study demonstrated that collagen had low digestibility and high swelling capacity. The human intervention showed a significant reduction associated with the collagen in body weight, body mass index (BMI), systolic blood pressure (SBP), and fatty liver index (FLI), and increased fat-free mass when compared with the control group. Overall, collagen supplementation at 20 g per day for 12 weeks reduced body weight, BMI, waist circumference, fat mass, FLI, and SBP in humans with overweight and obesity, which may be related to the increased sensation of fullness and satisfaction reported by the participants. 

Access to the study: https://pubmed.ncbi.nlm.nih.gov/39458544/  

Reference: López-Yoldi, M., Riezu-Boj, J. I., Abete, I., Ibero-Baraibar, I., Aranaz, P., González-Salazar, I., Izco, J. M., Recalde, J. I., González-Navarro, C. J., Milagro, F. I., & Zulet, M. A. (2024). Anti-Obesity Effects of a Collagen with Low Digestibility and High Swelling Capacity: A Human Randomized Control Trial. Nutrients, 16(20), 3550. https://doi.org/10.3390/nu16203550.  

Collagen peptide supplementation before bedtime reduces sleep fragmentation and improves cognitive function in physically active males with sleep complaints 

Insomnia is defined as nocturnal sleep disturbances and functional day time impairment. It is one of the most common sleep disorders, affecting 5-20% of adults. Inadequate sleep is associated with reduced quality of life, impaired cognition function, mood disturbances, and poorer physical and mental health. Accumulating evidence suggests that several nutrients interact with neurotransmitters and may help regulate the sleep-wake cycle, including the non-essential amino acid glycine, which activates N-methyl-D-aspartate (NMDA) receptors in the suprachiasmatic nucleus (SCN). Collagen peptides, which contain high amounts of glycine, are increasingly being examined for their potential therapeutic health effects in athletes. Research suggests that athletic populations may experience poorer sleep quality than the general population. Therefore, this study examined whether supplementing with a glycine-rich collagen peptide could enhance sleep quality in physically active males with self-reported sleep complaints. This randomized, crossover study recruited 13 athletic males with sleep complaints, as assessed by the Athens Insomnia Scale (AIS). Participants consumed 200 mL drinks that were either a placebo, or contained 15 g of collagen peptides, 1 hour before bedtime for 7 days. Sleep quality was measured with subjective sleep diaries and actigraphy for 7 nights, while polysomnographic sleep and core temperatures were recorded on night 7. Additionally, endocrine function, inflammation, and cognitive function were measured on night 7 and the following morning. Cognitive tests specifically measured simple reaction time, digit spans which assess attention and short-term recall, and the Stroop colour word test which assesses attention and processing speed, as well as the ability to inhibit cognitive interference. The intervention trials were separated by 7 days and preceded by a 7-night familiarization trial. This study demonstrated that supplementing with collagen peptide before bed resulted in less awakenings, as measured by polysomnography, compared to the placebo group. The 7-day average of subjective awakenings was lower with collagen peptide supplementation compared to the control group. Additionally, the proportion of correct responses on the baseline Stroop cognitive test were higher with collagen peptide supplementation on the morning following the seventh night. No differences between groups were observed in core temperature, endocrine function, inflammation, subjective sleepiness, and simple reaction time or digit span cognitive tests. Overall, this study demonstrates that 7 days of collagen peptide supplementation could enhance sleep quality in athletic populations with sleep complaints. Future studies are warranted to confirm these results. 

Access to this study: https://pubmed.ncbi.nlm.nih.gov/37874350/ 

Reference: Thomas, C., Kingshott, R.N., Allott, K.M., Tang, J.C.Y., Dunn, R., Fraser, W.D., Thorley, J., Virgilio, N., Prawitt, J., Hogervorst, E., Skarabot, J., & Clifford, T. (2024). Collagen peptide supplementation before bedtime reduces sleep fragmentation and improves cognitive function in physically active males with sleep complaints. European journal of nutrition, 63(1), 323-335. https://doi.org/10.1007/s00394-023-03267-w. 

Protein supplement tolerability and patient satisfaction after bariatric surgery  

Obesity has reached pandemic levels, increasing the risk of cardiometabolic diseases and cancer. Metabolic and bariatric surgery (MBS) is a popular procedure among obese individuals as it significantly reduces weight (about 20-30% total weight loss) and associated health risks. However, disproportional fat-free mass (FFM) loss is often experienced by patients after MBS, partly due to insufficient protein intake during the post-surgery recovery stage. Extreme FFM loss can be harmful since FFM is crucial for bodily functions like bone health, insulin resistance, and daily functioning. While guidelines recommend a daily protein intake of ≥ 60 g, the reduced gastric capacity and altered taste, smell, and digestion post-MBS make consuming protein-rich foods like meat and dairy challenging and less tolerated. Protein-enhancing strategies (PES) may subsidize protein intake insufficiency following MBS. This study evaluated the tolerability and satisfaction with consuming five PES and total protein intake in patients who have undergone MBS. Eighty-seven patients scheduled for bariatric surgery (i.e., a primary gastric bypass or sleeve gastrectomy) received one of the following: (1) whey powder, (2) hydrolyzed collagen powder, (3) plant-based powder, (4) protein-rich product, (5) protein gel, or control. Participants incorporated 30 g of powder, two gels, or a protein product into their diet. Participants dietary intake was assessed before and during PES use, while digital questionnaires assessed tolerability and satisfaction one week after the intervention. Over 60% of participants did not experience dietary complaints with PES intake, except for some concerns and non-usage of intervention due to taste aversion (58%). The study results showed that hydrolyzed collagen scored the highest on tolerability and satisfaction. The PES group had a significantly increased overall protein intake (p = 0.002) from baseline compared to the protein intake difference reported in the control group (p = 0.019). Altogether, this study showed that different PES are well tolerated and may improve protein intake in post-MBS, with hydrolyzed collagen as the most tolerated and whey leading to the greatest increase in protein intake. Taste was the biggest challenge regarding PES use in post-MBS patients; as such, future interventions should target this concern.  

Access to the study: https://pubmed.ncbi.nlm.nih.gov/39243332/  

Reference: Luijpers, C. L. H., Nuijten, M. A. H., Groenhuijzen, E. J., van Hogezand, L. L., Monpellier, V. M., Eijsvogels, T. M. H., & Hopman, M. T. E. (2024). Protein Supplement Tolerability and Patient Satisfaction after Bariatric Surgery. Obesity surgery, 34(10), 3866–3875. https://doi.org/10.1007/s11695-024-07462-4.  

Influence of collagen peptide supplementation on visible signs of skin and nail health and -aging in an East Asian population: A double blind, randomized, placebo-controlled trial 

Skin aging is characterized by structural and morphological changes altering the skin’s health, integrity, and functionality, leading to skin sagging and wrinkle formation. Collagen is abundant in the ECM, contributing to the skin’s elasticity and viscosity. However, with age, there is a progressive loss of collagen quality and quantity, along with increased fragmentation. Recent studies suggest that different types of collagens may affect skin health and aging differently, influenced by population variations in skin characteristics and lifestyle habits. This randomized, double-blinded, placebo-controlled trial assessed the effect of a collagen peptide dietary supplement on skin aging in East Asians. Eighty-five healthy Asian women (aged 43-65 years) randomly received either a 5 g porcine collagen supplement (CP) or placebo (maltodextrin, 5 g). All subjects used a specific face cream for 28 days before and throughout the supplementation period to standardize daily skin care and to ensure an equal baseline for the CP efficacy assessment on skin parameters. At baseline, day 28, and day 84, numerous skin and nail aging markers were assessed, including dermis density, skin moisture and elasticity, wrinkle visibility, beauty perception, and nail color. The study found significant improvement of dermis density and skin moisture after 84 days in the CP group compared to placebo. The study also reported positive effects on skin elasticity, wrinkle visibility, nail color, and overall beauty perception after 28 days of CP supplementation, while the placebo group reported the same effects after 84 days. As such, this study supports the daily use of CP supplementation alongside standardized skincare to positively affect visible signs of skin and nail aging in East Asians.  

Access to the study: https://pubmed.ncbi.nlm.nih.gov/39143887/  

Reference: Vleminckx, S., Virgilio, N., Asserin, J., Prawitt, J., & Silva, C. I. F. (2024). Influence of collagen peptide supplementation on visible signs of skin and nail health and -aging in an East Asian population: A double blind, randomized, placebo-controlled trial. Journal of cosmetic dermatology, 23(11), 3645–3653. https://doi.org/10.1111/jocd.16458.  

Bottom Line  

Collagen is the most abundant protein found in the ECM, providing strength, integrity, and structural organization. It is essential for the body’s structural, mechanical, organizational, and tissue-building properties. Unfortunately, collagen degrades disproportionally with age, requiring external interventions to overcome this loss. Increasing evidence supports the positive effects of collagen supplementation on skin and orthopedic health, making collagen a beneficial ingredient in food, pharmaceutical, and cosmetic products.